code: def test_exclude_unknowns_empty_error(self):
      try:
          Dataset.build(self.triplet_data, exclude_unknowns=True)
      except ValueError:
          assert True
  
imports: import unittest
  import numpy
  import numpy.testing
  from cornac.data import BasketDataset, Dataset, SequentialDataset, Reader
label_desc: Use image node_id 4 for calling the TestDataset obj's underlying member method code with example usage: obj.test_exclude_unknowns_empty_error() without return types